The treatment of various fibrous substrates, notably carpets, textiles, leathers and papers, with fluoroaliphatic group-containing polymers and oligomers enabling them to retain their original aesthetic appeal (e.g., to render them repellent to water- and oil-based stains and resistant to soils) has been known in the art for many years. Mason Hayek, Waterproofing and Water/Oil Repellency, in 24 KIRK-OTHMER ENCYCLOPEDIA OF CHEMICAL TECHNOLOGY 448–65 (3d ed. 1979), for example, provides a general overview of anti-staining and anti-soiling technology for fibrous substrates.
Fluorochemicals known to be useful for treating carpets include ester oligomers, as disclosed in U.S. Pat. No. 4,264,484 (Patel), carbodiimide oligomers, as disclosed in U.S. Pat. No. 3,896,251 (Landucci), guanidine oligomers, as disclosed in U.S. Pat. No. 4,540,497 (Chang), allophanate oligomers, as disclosed in U.S. Pat. No. 4,606,737 (Stem), oxazolidinone oligomers, as disclosed in U.S. Pat. No.5,025,052 (Crater et al.), and acrylic polymers, as disclosed in U.S. Pat. No. 3,916,053 (Sherman et al.).
Fluorochemical urethane, urea, and biuret oligomers have often become the treatment of choice for carpets due to their durable soil-resistance properties. For example, U.S. Pat. No. 3,398,182 (Guenthner et al.) discloses the use of fluoroaliphatic urethanes in making oleophobic and hydrophobic coatings that resist removal by abrasion.
U.S. Pat. No. 5,350,795 (Smith et al.) discloses substantially organic solvent-free, aqueous solutions or dispersions for treating textile fibers and fabrics to impart oil and water repellency without thermal treatment comprising (a) a fluorochemical acrylate copolymer comprising the reaction product of a fluorinated acrylate monomer, polyoxyalkylene glycol acrylate or methacrylate, and polyoxyalkylene glycol diacrylate or dimethacrylate, and (b) a polyalkoxylated polyurethane having pendant perfluoroalkyl groups comprised of an aliphatic or aromatic tri- or higher order isocyanate, a fluorinated alcohol, amine or mercaptan, and a poly(oxyalkylene) diol or dithiol, the polyurethane having a weight average molecular weight of over 40,000.
U.S. Pat. Nos. 5,410,073 (Kirchner), 5,411,766 (Kirchner) and 5,414,111 (Kirchner) each describes polyfluoro nitrogen containing organic compounds made by reacting (a) at least one polyisocyanate or mixture of polyisocyanates that contain at least three isocyanate groups per molecule with (b) at least one fluorochemical compound which contains per molecule (i) a single functional group having one or more Zerewitinoff hydrogen atoms and (ii) at least two carbon atoms each of which contains at least two fluorine atoms, the amount of fluorochemical compound being sufficient to react with 95% to 40% of the isocyanate groups, (c) then reacting the reaction product of (a) and (b) with water in an amount to react with the about 5% to about 50% of remaining isocyanate groups; such compounds when applied to fibers and fabrics reportedly provide durable water-, oil- and soil-repellent and/or soil release properties to the fibrous substrate. U.S. Pat. No. 5,414,111 teaches specifically the use of a monofunctional, non-fluorinated organic compound as an optional reactive component.
U.S. Pat. No. 4,504,401 (Matsuo et al.) describes a stainproofing agent represented by the general formula (Rf—X-A-CONH)aW(NHCO-A′-Z)3−a, wherein Rf is a polyfluoroalkyl group having from 1 to 20 carbon atoms. X is —R—, —CON(R1)-Q- or —SO2N(R1)-Q-(where R is a divalent alkylene group, R1 is a hydrogen atom or lower alkyl group and Q is a divalent organic group), each or A and A′ is —O—, —S—, or —N(Z′)— (where Z′ is a hydrogen atom or a monovalent organic group), Z is a monovalent organic group, W is a trivalent organic group and a is an integer of 1,2 or 3.